Ension, Inc. is seeking to complete the development of a pulsatile pediatric blood pump, CardioFIowPQ, that is specifically designed for use in neonatal and small-sized pediatric patients, less than 10kg body weight. The Ension device supports beat rates up to 120 BPM, while pumping up to 2.0 Lpm through pediatric-sized cannulas. Increasingly, evidence suggests that pulsatile flow is more physiologic and may in fact be beneficial to pediatric patients as compared to continuous flow blood pumps. The remaining goals for this project are the optimization of pumping functions to maximize pump output at the lowest rotational speed. For this task we are employing computer aided engineering to optimize housing design and a comprehensive series of in vitro and in vivo experiments to optimize device design and prove safe and reliable operation. Further refinements will be made to the controller and control algorithms developed in Phase I to provide a pulse wave closely duplicating that of pediatric patients. Ension is proposing to work with the University of Louisville, Cardiovascular Research Laboratory to perform this project. This laboratory has developed a highly instrumented mock loop of the pediatric circulation that will be used to simulate the most commonly occurring conditions that require circulatory support. Further experiments will include acute in vivo tests for hemodynamic evaluation and chronic in vivo tests to determine reliable operation and hemorheologic response to long-term use. Market research indicates that pulsatile flow, priming volume, and foreign surface area are among the major concerns facing pediatric cardiovascular surgeons. The Ension CardioFIow PQ blood pump addresses all of these issues, and if successful, would be quickly accepted by perfusionists and surgeons.